FIG. 1 illustrates the general constitution of a dead-tank circuit breaker 1. The dead-tank circuit breaker 1 comprises six bushings 2, two of which are to be seen in FIG. 1.
It also comprises a metal tank 3 which houses an interrupter 4 and which is filled with insulating gas. The tank 3 is provided with legs forming a supporting frame 6.
The bushings 2 are connected to the interrupter 4 and they are disconnected from it via plug-in connections 5.
The extraction procedure of the interrupter 4 from the tank 3 requires first the removal of the bushings 2. The insulator shell 14 of the bushing 2 and the central conductor 12 of the bushing 2 are lifted so that the conductor tip 13 disengages the plug-in connection 5.
Once the bushings 2 have been lifted along arrows 70 and 71, the interrupter is removed from the tank along arrow 74.
It is difficult to remove an interrupter 4 from the tank 3 according to this known method.
The bushings 2 are indeed heavy and cumbersome. They need to be safely maintained and removed with a constant angle of tilt from the tank 3.